Shimmy and vibration in the E21 front end is often linked to the condition of the steering bushings. These bushings wrap around the steering rack when it's mounted to the front subframe (and sheetmetal cover). Worn bushings allow the rack to twist and shift. These are original rubber bushings that are a match to the original spec.
This is a Genuine BMW E21 steering mount with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.
BMW Fitments:
3 Series
E21 (75-83) > 320i
E21 (75-83) > 323i